1. Field of Invention
The present invention relates generally to improvements in clamping devices and, more particularly, to a new and improved device for securely clamping items having various shapes and sizes and for placing the items in direct contact with each other.
2. Description of the Prior Art
It is often desirable to selectively clasp, brace or fasten items together. For this reason, a multitude of clamps or fasteners have been created, some of which are spring loaded to urge the generally oppositely facing engaging surfaces towards one another to grasp an item therebetween. In other forms, screw or other biasing elements may be used to bring the engaging surfaces together.
One common application of clamping devices is for the quick and easy removal of electrical wiring to various electrical terminals. In this application, the clamping device acts as an electrical connector which can be affixed to each end of the wiring to connect the items, usually a power source and the powered item together. The connector is designed to grasp and retain the electrical terminal which is usually formed as extending posts or tabs on the powered item. In this arrangement, the clamp-like connector can be easily removed or placed on the terminal, eliminating the need for a soldered joint or other similar connector.
An alligator clip is one example of a clamping device that can be used as an electrical connector. The clip generally includes a pair of opposing jaw members that are pivotally mounted to each other, each jaw having opposing serrated surfaces. A helical spring provides a biasing force that urges the jaws towards one another and maintains the jaws in contact with the item that is placed therebetween.
One problem associated with the alligator clip connector is its inability to securely engage larger sized or odd shaped terminals. Generally, as the engaging jaws of alligator clips are further separated, the helical spring is displaced further from its rest position, increasing the bias between the jaws. However, as the jaws are opened more and more, the engaging surfaces are increasingly angled relative to each other. This increased angle, in combination with the increased biasing force, makes it more difficult for the alligator clips to securely engage the larger shaped terminals. This is best illustrated in the difficulty which arises when an alligator-type clip is attached to an automobile battery terminal.
Another problem may arise if the connector is used with testing or measuring instrumentation. For example, ohm or volt meters have positive and negative leads which terminate at an electrically sensitive probe that should be in direct contact with the item being tested, e.g., a battery or a piece of wire. If an alligator clip or other type of clasping connector is connected to the probe, without having the probe in direct contact with the test item, the readings of the testing instrument may be impaired. Thus, the testing instrument may provide a more accurate reading if the probes are directly connected to the test material.
Still another problem that may arise from the use of electrically conductive electrical connectors is the possibility that the user may receive an electrical shock if he or she inadvertently touches an exposed surface of a "hot" connector. Responsive to this problem, non-conductive covers have been formed around the connector to provide an insulating layer to protect its user. However, these covers eventually fray and crack with age, reducing their effectiveness.
Hence, those concerned with the development and use of electrical connectors have long recognized the need for a connector for directly connecting a lead to the item being tested along with the need for an improved connector that can be clamped to terminals of varying shapes and sizes. The present invention clearly fulfills all of these needs.